As we come on the air we are learning more about what happened at the giant shopping mall in new jersey when another young man with a weapon walked in and sent people running for their lives. Miraculously no one was hurt. Here it is, the garden state plaza mall, last night teeming with shoppers, tonight the long stretch of shops empty, closed down by police, a crime scene. Once again we are left asking why. Tonight you will hear from the gunman's family and friends. Abc's gio benitez starts us off. Reporter: Terror and confusion -- at one of the nation's biggest malls, just minutes before closing time. 9:19 pm, shoppers at the garden state plaza mall in paramus, new jersey making their final byes when they saw a figure right out of the movies. He was dressed in all black with a gun in his hand. Reporter: Investigators say that man was 20-year-old rich shoop, carrying a gun he stole from his brother. He walked out in front of the nordstrom department store and started firing into the air. Chaos as 1,000 shoppers and employees ran for cover. Police evacuating hundreds. As soon as I came upstairs the mall security guy was screaming at me to get out. Reporter: It took them six hours to find his body. Shoop had shot himself in a secluded part of the mall. Last night the police descending at his house. Today shoop's brother kevin speaking out. My brother intended to harm nobody but himself. He just sadly decided to make an act of -- an act of I guess self-indulgence by taking his own life. Reporter: Police say shoop was a drug user, heroin and the club drug molly and now we're learning he may have maid a cry for help, texting his best friend's girlfriend just three hours before he went to that mall. In so many ways you were perhaps the last person to speak with him. Yes. And I just really wish that i would have answered him. I just really do because i really think that maybe this could have gone differently. Reporter: She read to us a string of bizarre text messages that she said shoop wrote to him yesterday. I'm either going to go away, die or make a run for it. Cops have been watching my house for four days. I only have maybe one more day before they come for it and then the last message said sorry. Reporter: Friends tell me shoop had been paranoid and quiet for weeks. The problem that some of those friends tell me they just ignored that paranoia. So they weren't clear warning signs to family or friends? They say so. Gio benitez reporting live from the scene tonight. Thank you.

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